简单的图书管理系统

import json import os # 文件路径 USER_FILE = "users.json" BOOK_FILE = "books.json" # ========== 数据初始化与读写 ========== def load_data(file_path): """加载json文件，文件不存在则返回空列表""" if not os.path.exists(file_path): return [] with open(file_path, "r", encoding="utf-8") as f: return json.load(f) def save_data(file_path, data): """保存数据到json文件""" with open(file_path, "w", encoding="utf-8") as f: json.dump(data, f, ensure_ascii=False, indent=2) # 初始化默认账号（首次运行自动创建） def init_default_user(): users = load_data(USER_FILE) if len(users) == 0: # 管理员账号 users.append({"username": "admin", "password": "123456", "role": "admin"}) # 普通读者账号 users.append({"username": "reader", "password": "123", "role": "reader"}) save_data(USER_FILE, users) # ========== 用户登录模块 ========== def login(): print("=" * 30) print(" 图书管理系统 登录") print("=" * 30) username = input("请输入账号：") password = input("请输入密码：") user_list = load_data(USER_FILE) for user in user_list: if user["username"] == username and user["password"] == password: print(f"\n登录成功！欢迎你，{username}") return user print("账号或密码错误！") return None # ========== 管理员功能 ========== def admin_menu(): while True: print("\n===== 管理员菜单 =====") print("1. 添加图书") print("2. 修改图书信息") print("3. 删除图书") print("4. 查询所有图书") print("5. 返回登录界面") choice = input("请输入操作序号：") if choice == "1": add_book() elif choice == "2": edit_book() elif choice == "3": del_book() elif choice == "4": show_all_books() elif choice == "5": break else: print("输入无效，请重新选择！") def add_book(): books = load_data(BOOK_FILE) book_id = input("输入图书编号：") # 检查编号是否重复 for b in books: if b["id"] == book_id: print("该图书编号已存在，添加失败！") return book_name = input("输入图书名称：") author = input("输入作者：") category = input("输入图书分类：") num = int(input("输入库存数量：")) new_book = { "id": book_id, "name": book_name, "author": author, "category": category, "stock": num, "borrow_user": None # 当前借阅人，无人借阅为None } books.append(new_book) save_data(BOOK_FILE, books) print("✅ 图书添加成功！") def show_all_books(): books = load_data(BOOK_FILE) if not books: print("暂无图书数据！") return print("\n编号\t书名\t作者\t分类\t库存\t借阅人") print("-" * 60) for b in books: user = b["borrow_user"] if b["borrow_user"] else "无" print(f"{b['id']}\t{b['name']}\t{b['author']}\t{b['category']}\t{b['stock']}\t{user}") def edit_book(): books = load_data(BOOK_FILE) bid = input("输入要修改的图书编号：") for book in books: if book["id"] == bid: book["name"] = input("输入新书名：") book["author"] = input("输入新作者：") book["category"] = input("输入新分类：") book["stock"] = int(input("输入新库存：")) save_data(BOOK_FILE, books) print("✅ 修改完成！") return print("未找到该编号的图书！") def del_book(): books = load_data(BOOK_FILE) bid = input("输入要删除的图书编号：") for i, book in enumerate(books): if book["id"] == bid: books.pop(i) save_data(BOOK_FILE, books) print("✅ 删除成功！") return print("图书不存在！") # ========== 读者功能（借阅/归还） ========== def reader_menu(current_user): while True: print("\n===== 读者菜单 =====") print("1. 查看全部图书") print("2. 借阅图书") print("3. 归还图书") print("4. 返回登录界面") choice = input("请选择操作：") if choice == "1": show_all_books() elif choice == "2": borrow_book(current_user["username"]) elif choice == "3": return_book(current_user["username"]) elif choice == "4": break else: print("输入错误！") def borrow_book(username): books = load_data(BOOK_FILE) bid = input("输入要借阅的图书编号：") for book in books: if book["id"] == bid: if book["stock"] <= 0: print("库存不足，无法借阅！") return if book["borrow_user"] is not None: print("这本书已被别人借走！") return book["stock"] -= 1 book["borrow_user"] = username save_data(BOOK_FILE, books) print(f"✅ {username} 借阅成功！") return print("找不到这本图书！") def return_book(username): books = load_data(BOOK_FILE) bid = input("输入归还图书编号：") for book in books: if book["id"] == bid: if book["borrow_user"] != username: print("你没有借阅这本书，无法归还！") return book["stock"] += 1 book["borrow_user"] = None save_data(BOOK_FILE, books) print("✅ 归还成功！") return print("图书不存在！") # ========== 程序主入口 ========== def main(): # 初始化管理员与读者账号 init_default_user() while True: current_user = login() if not current_user: continue # 根据角色进入不同菜单 if current_user["role"] == "admin": admin_menu() else: reader_menu(current_user) if __name__ == "__main__": main()